ES2837075T3 - A method of manufacturing a fuel component - Google Patents

Abstract

A method of manufacturing a diesel fuel composition, comprising a. a hydrotreating step, comprising catalytically hydrotreating renewable raw material comprising fatty acids, triglycerides, fatty acid esters or combinations thereof in n-paraffins; b. an isomerization step, comprising catalytically isomerizing the n-paraffins into branched-chain paraffins to obtain a hydrotreated renewable fuel component, wherein the amount of the paraffin component in the C15-C18 carbon number range is at least 70% in weight, and the iparaffin / n-paraffin ratio of the hydrotreated renewable component is at least 2.2 w / w; c. adding a fossil fuel component to the hydrotreated renewable fuel component; and d. add 2-EHN at a concentration in the range of 100-1000 mg / kg; where stage b. It is carried out in the absence of the hydrotreating catalyst used in step a.

Description

DESCRIPTION

A method of manufacturing a fuel component

Field of the invention

The present invention is related to the field of renewable fuel components and to the methods for manufacturing them.

Background

The cetane number describes the compression ignition behavior of a diesel fuel. High cetane levels allow for faster ignition in a diesel engine. The cetane number is a requirement in Diesel Fuel Standards EN590: 2013 (5.5.2) and ASTM D9752017. The requirement in Diesel Standard E ⁿ 590: 2013 (5.5.2) is minimum 51 and in ASTM D975 2017 40, correspondingly. In diesel fuels, cetane number targets can be achieved by refining, blending, or adding a cetane index improver, such as 2-ethylhexyl nitrate (2-EHN). However, the high dosage of 2-EHN causes an unpleasant odor in diesel fuel. There are also indications that 2-EHN negatively affects diesel NOx emissions and additionally according to EN590: 2013 (5.5.2), the cetane improver can cause increased carbon residues. Therefore, there is a need to provide fuel compositions with a high cetane number, while reducing the deleterious effects associated with cetane number improvers.

EP1956070 describes a method for producing a gas oil composition. The resulting product requires at least 500 ppm of diesel specific cetane index improver to obtain a satisfactory cetane number [0142].

US2008033220 describes an increasing cetane number of GTL, a fuel derived from Fischer-Tropsch. EP 2333032 A1 describes a method for manufacturing a diesel fuel composition.

Summary

According to the first aspect of the invention, there is provided a method of manufacturing a diesel fuel component as defined in claim 1.

According to the second aspect of the invention, there is provided a diesel fuel component as defined in claim 8.

According to the third aspect of the invention, there is provided a use of the diesel fuel component of the second aspect to increase the cetane number and improve the cold properties of a diesel fuel. According to the fourth aspect of the invention there is provided a fuel composition comprising: a. the diesel fuel component of the third aspect; and B. a fossil fuel component.

An advantage achieved by the invention is the efficient increase of the cetane number in fuel blends comprising the present diesel fuel component, particularly in fuel blends for diesel engines. As evidenced by the Examples, the cetane number of diesel fuel compositions could be increased by including the present diesel fuel component therein.

Another advantage achieved by the invention is that a low amount of a cetane number improver needs to be used in fuel blends to achieve a desired cetane number, such as a cetane number required by a diesel fuel standard. Fig. 2 shows the results of an example where 2-EHN was used as a cetane number improver: a dose of 250 mg / kg resulted in a greater increase in the cetane number in a mixture comprising a component of hydrotreated renewable fuel, compared to a GTL component. Therefore, when using the present invention, a lesser amount of the cetane index improver can be used to increase the cetane number to a desired value, which helps to prevent or lessen the harmful effects of the cetane index improvers, such as 2-EHN. In particular, increased NOx emissions caused by larger amounts of 2-EHN can be avoided.

Another advantage of the invention is that a fuel composition can be obtained which simultaneously has a good cetane number and also good cold properties. By the invention it is possible to obtain e.g. eg, diesel fuel blends comprising fossil fuels and having such characteristics. Diesel fuel blends of this type are particularly good for use in cold climates.

Another advantage of the invention is that since step b. is carried out in the absence of the catalyst used in step a., problems related to the use of a one-phase process, such as cracking and poor i-paraffin: n-paraffin ratio can be avoided. Therefore, the method is particularly useful to obtain a diesel fuel component suitable for improving the properties of diesel fuels used in cold climates.

The present diesel fuel component can be mixed with fossil diesel fuel or renewable diesel fuel in a desired amount, depending on the desired properties of the fossil fuel or renewable diesel fuel. E.g. When the blend comprises diesel fuel with a low cetane number, a higher proportion of the diesel fuel component can be used to increase the cetane number of the blend. Correspondingly, if the cold properties of the fossil fuel are to be improved, a fuel component having a higher i-paraffin / n-paraffin ratio, as defined below, can be used. The increase in cetane number achieved by the present invention was synergistic and much greater compared to the effect that can be obtained using other fuel components, such as GTL. Without being bound by theory, the observed synergistic effect is caused by the manufacturing process of the diesel fuel component and the characteristics of the hydrogen treated renewable fuel component and the cetane number improver. The synergistic effect was confirmed experimentally when the inventors used a renewable fuel component having a carbon number distribution similar to that of 1HVO. The inventors successfully used this finding to define a fuel composition comprising a hydrogen treated renewable fuel component, fossil fuel, and a cetane improver.

The present diesel fuel component is also advantageous in that it has high density, viscosity, and lubricity.

Brief description of the figures

Fig. 1 shows the profile of paraffinic components for renewable fuels (RN2 and RN2) and GTL fuels. CP refers to the cloud point.

Fig. 2 shows the effect of different amounts of 2-EHN addition on GTL and renewable fuel blends (RN2).

Fig. 3 graphically shows the improvement of the cetane number in a mixture of renewable fuel (RN) and fossil fuel compared to a fossil diesel fuel.

Fig. 4 graphically shows the improvement of the cetane number in a mixture of renewable fuel (RN) and fossil fuel compared to a fossil diesel fuel.

Fig. 5 shows a detailed distribution of paraffinic components in renewable fuels (RN2) and GTL fuels.

Detailed description

In one embodiment, the present renewable raw material comprises vegetable oil, wood and / or other vegetable based oil, animal fat, fish fat and / or fish oil, algae oil, microbial oil, plant-contained fats obtained by manipulation. genetics, recyclable waste, recyclable waste, or a combination thereof.

In one embodiment, the present renewable raw material comprises rapeseed oil, rapeseed oil, canola oil, talloil, sunflower oil, soybean oil, hemp oil, olive oil, linseed oil, mustard oil, palm oil, peanut oil, castor oil, coconut oil, lard, tallow, grain, fats contained in milk or a combination thereof.

The cetane index improver is 2-EHN.

In one embodiment in the present hydrotreated renewable fuel component, the amount of the paraffinic component in the C ¹⁵ -C ¹⁸ carbon number range is more than 80% by weight, most preferably more than 90% by weight. Such carbon number distribution is a characteristic of the present renewable fuel component that shows a synergistic improvement of the cetane number with 2-EHN.

In one embodiment, the i-paraffin / n-paraffin ratio of the present hydrotreated renewable component is at least 2.3 w / w, at least 3 w / w, or at least 4 w / w.

In one embodiment, the renewable raw material is fed to step a. of hydrotreating in a feed comprising less than 10 p-ppm of alkali metals and alkaline earth metals calculated as elemental alkali metals and elemental alkaline earth metals, less than 10 p-ppm of other metals calculated as elemental metals, and less than 30 p-ppm of phosphorus calculated as phosphorus.

In one embodiment, the feed comprises a fresh feed of the renewable raw material and a feed of a diluent agent, and wherein the diluent: fresh feed ratio is 10-30: 1, preferably 12-25: 1 , and wherein the diluting agent is selected from hydrocarbons and recycled products of the process, or a mixture thereof.

In one embodiment in the hydrotreating step, the pressure is selected or varied in the range of 2-15 MPa, preferably 3-10 MPa, and the temperature is selected or varied in the range of 200-500 ° C, preferably 280- 400 ° C.

In one embodiment, the hydrotreating step is carried out in the presence of a hydrotreating catalyst, which contains a Group VIII and / or Group VIB metal of the Periodic System.

In one embodiment, the hydrotreating catalyst is a supported Pd, Pt, Ni, NiMo, or CoMo catalyst and the support is alumina and / or silica.

In another embodiment, the isomerization catalyst contains a molecular sieve.

In another embodiment, the isomerization catalyst contains AhO ³ or SiO ² .

In another embodiment, the isomerization catalyst contains SAPO-11 or SAPO-41 or ZSM-22 or ZSM-23 or ferrierite; and Pt or Pd; and Al2O3 or SiO ² .

The cetane index improver is added to the hydrotreated renewable fuel component obtained in step b.

In one embodiment, steps a. and b. are carried out repeatedly by feeding the recycled product from step b. in stage a. until obtaining the desired degree of hydration and isomerization of the renewable raw material. In the hydrotreated renewable fuel component the amount of the paraffinic component in the carbon number range C ¹⁵ -C ¹⁸ is at least 70% by weight and the i-paraffin / n-paraffin ratio of the hydrotreated renewable component is at least 2, 2 p / p, at least 3 p / p or at least 4 p / p.

In one embodiment, the present diesel fuel component has a cloud point of at least -10 ° C. In the present diesel fuel composition, the cetane index improver is 2-EHN.

In one embodiment in the present fuel composition, the content of the hydrotreated renewable fuel component in the fuel composition is in the range of 5-90% by volume, more preferably in the range of 20-80% by volume. This amount is advantageous because it reduces the harmful effects of 2-EHN while raising the cetane number of the mixture to the desired level.

In another embodiment, the amount of the cetane improver used in the present fuel composition is less than 500 mg / kg, such as about 450, 400, 350, 300, 350, 300, 250, 200, 150, or 100 mg. / kg. In one embodiment, the amount is selected to be within the range of 100-450 mg / kg, 100-400 mg / kg, or 100-300 mg / kg.

In the present fuel composition, the cetane enhancer is 2-EHN, and the amount of 2-EHN is selected from the range of 100-1000 mg / kg, more preferably from the range of 100-400 mg / kg.

2-Ethylhexyl Nitrate (2-EHN) is a cetane number improver, which can be used to improve, that is, increase the cetane number of fuels, such as diesel fuels.

GTL is a Fischer-Tropsch derived fuel that has a cloud point similar to that of an HVO derived fuel. GTL is characterized by a wide distribution of paraffinic hydrocarbons in the C ⁹ -C ^{24 range} . GTL typically has a cetane number in the range 73-81 (Aatola et al. Hydroteated Vegetable Oil (HVO) as a Renewable Diesel Fuel: Trade-off between NOx, Particulate Emission, and Fuel Consumption of a Heavy Duty Engine, SAE International 2008-01-2500).

The inventors surprisingly found that although HVO and GTL as such have similar properties with respect to cetane number, cloud point and density, when used in blends comprising HVO or GTL, a fossil fuel component and an index improver of cetane, a significantly different effect on the cetane number is achieved. A smaller addition of the cetane improver in a fuel mixture containing HVO is sufficient to increase the cetane number of the fuel mixture to a level obtained in a fuel mixture containing GTL only with an addition of the fuel improver. much higher cetane number. Consequently, when using HVO in the mix, a much lower addition of cetane index improver is needed, which reduces consumption and its harmful effects. The GTL and HVO components were analyzed in more detail in Example 1. Analysis revealed significant differences in the carbon number profiles of these two fuel components. As evidenced in the Examples and shown in Figs. 1 and 5, the total paraffin distributions of these components are markedly different, resulting in different properties. Without being bound by theory, the results indicate that the characteristic paraffin profile of the HVO component provides a synergistic effect with 2-EHN on the cetane number in fuel blends.

In one embodiment, the biological raw material comprises vegetable oil, animal fat, fish fat, fish oil, algae oil, microbial oil and / or wood and / or other vegetable-based oil, as well as recyclable waste and / or residues. , or a combination thereof. In one embodiment, the hydrotreated renewable fuel component obtained after hydrotreating and isomerization comprises HVO, or consists of HVO. Hydrotreating can be used to produce bio-based middle distillate fuels. HVO fuels are sometimes referred to as "renewable fuels" rather than "bio-diesel", which is a term reserved for fatty acid methyl esters (FAME). Chemically hydrotreated vegetable oils are mixtures of paraffinic hydrocarbons and have a very low amount of sulfur and aromatic components.

The present diesel fuel component is preferably manufactured using a two-stage process, comprising hydrogenation followed by isomerization. If a manufacturing process that uses a single-stage process is used where the hydrogenation and isomerization stages are not carried out in separate stages, damaging cracking can occur resulting in a loss of long-chain hydrocarbons and a change from the carbon number profile to lower carbon numbers. One-step hydrogenation and isomerization can also result in a lower i-paraffin: n-paraffin ratio compared to a two-step process where these steps are carried out sequentially. In a preferred embodiment, the two-stage process is carried out by hydrogenating in n-paraffins, followed by catalytic isomerization in iparaffins. Such a two-stage process is described in FI1002488.

In one embodiment of the present hydrotreated renewable fuel component, the amount of i-paraffins increases compared to the amount of i-paraffins after hydrogenation and before isomerization. In another embodiment, the carbon number distribution does not change, or does not change substantially, during isomerization. In a preferred embodiment, the amount of paraffins in the C ³ -C ¹⁴ carbon number range does not increase substantially during isomerization.

In one embodiment, the present renewable fuel component has a cloud point of at least -10 ° C. Such a cloud point is particularly useful for fuels intended for use in cold environments, such as winter grade diesel fuel. In one embodiment, the cloud point is approximately -11, -12, -13, -14, -15, -16, -17, -18, -19, -20, -21, -22, -23, - 24, -25, -26, -27, -28, -29 or -30 ° C.

The i-paraffin / n-paraffin ratio of the present hydrotreated renewable component is at least 2.2 w / w, such as about 2.2, 2.3, 2.4, 2.5, 2.6, 2.7 , 2,8, 2,9, 3, 4, 5, 6, 7, 8, 9 or 10. Fossil fuel component means a naturally occurring component or composition that is derived from non-renewable sources . Examples of such non-renewable resources include petroleum oil / gas, shale oil / gas, natural gas or coal deposits and the like, and combinations thereof, including any hydrocarbon-rich deposits that can be utilized from sources terrestrial / underground. The term fossil also refers to material recycled from non-renewable sources.

In one embodiment, the fossil fuel component is a fossil middle distillate, preferably fossil diesel. Diesel fuel in general is any liquid fuel suitable for use in diesel engines, where the ignition of the fuel takes place without spark as a result of compression of the intake air mixture and then fuel injection. In one embodiment, the present diesel fuel is fossil diesel. The most common type of diesel fuel is a specific fractional distillate of fossil fuel, preferably petroleum fuel oil. Distillation characteristics define how fuel evaporates when sprayed into the combustion chamber of a diesel engine. The Standards (eg EN590: 2013 (5.5.2)) include information on typical distillation curves.

To distinguish them from alternative non-petroleum diesel fuels, petroleum-derived diesel is referred to herein as fossil diesel. It can also be called, e.g. ex. petroleum diesel, mineral diesel or petroleum distillate. The fossil diesel can comprise atmospheric or vacuum distillates. The distillate may comprise cracked gas oil or a mixture of any proportion of thermal or catalytically cracked or first run distillates. The distillate fuel can undergo further processing, such as hydrogen treatment or other processes to improve the properties of the fuel. Normally, fossil diesel comprises naphthenic components in 10-50% by weight, monoaromatic components in 5-30% by weight, other polyaromatic components in 0-8% by weight and paraffins in 10-50% by weight.

In one embodiment in the present fuel composition, the hydrotreated renewable fuel component comprises or consists of hydrotreated vegetable oil, hydrotreated animal fat, hydrotreated fish fat, hydrotreated fish oil, hydrotreated algae oil, hydrotreated microbial oil, hydrotreated wood and / or other vegetable oil, waste and / or hydrotreated recyclable waste or a combination thereof. An advantage of the embodiment is that when said materials are used in a hydrotreatment, a renewable fuel component is obtained, which, together with a cetane index improver, is capable of synergistically increasing the cetane number of the fuel compositions that They comprise the fossil fuel component. In addition, the increase in carbon waste can be minimized.

In the present hydrotreated renewable fuel component, the amount of paraffinic components in a range of C ¹⁵ -C ¹⁸ carbon numbers is at least 70% by weight, more preferably more than 80% by weight, which more preferably more than 90% by weight. When using a hydrotreated renewable fuel component having such a paraffinic component profile together with 2-EHN, the cetane number of the fuel composition increases.

In one embodiment of the present hydrotreated renewable fuel component, the amount of paraffinic components in the C ³ -C ¹⁴ carbon number range is less than 25% by weight, such as less than 20% by weight, less than 10% by weight, or less than 7% by weight. Optionally, in the hydrotreated renewable fuel component, the amount of paraffinic components in the C ¹⁹ -C ²⁴ carbon number range is less than 25% by weight, such as less than 20% by weight, less than 10% by weight or less than 5% by weight. In one embodiment, the present hydrotreated renewable component has a cetane number of at least 70, preferably at least 80. By using a hydrotreated renewable component that has a high cetane number, a smaller addition of hydrotreated renewable component and an enhancer of the Cetane number provide a desired increase in a mixture comprising a fossil fuel component.

In one embodiment, the present hydrotreated renewable fuel component comprises hydrotreated vegetable oil, hydrotreated wood and / or other vegetable based oil, hydrotreated animal fat, hydrotreated fish oil and fat, hydrotreated seaweed oil, hydrotreated microbial oil, hydrotreated recyclable waste. , hydrotreated recyclable waste, or a combination thereof.

In one embodiment, the content of the hydrotreated renewable fuel component in the present fuel composition is in the range of 5-90% by volume, more preferably in the range of 20-80% by volume. In one embodiment, the content of the hydrotreated renewable fuel component in the fuel composition is 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or 80% by volume.

In one embodiment, the present fuel composition is a fuel composition obtainable by mixing the diesel fuel component with fossil diesel fuel.

In one embodiment, the present diesel fuel component does not contain fatty acid methyl esters. The final fuel composition may contain additional refinery and performance components such as lubrication, cold flow, antistatic and detergent components.

Examples

The following examples are provided to illustrate various aspects of the present invention. They are not intended to limit the invention, which is defined by the appended claims.

Example 1: Profile of the number of carbons of a renewable fuel and GTL

Carbon number profiles of HVO as a renewable fuel and GTL were analyzed by gas chromatography (GC). The results are shown in Fig. 1 and Fig. 5.

Example 2: Analysis of a renewable fuel and GTL

The physical properties of HVO as a renewable fuel and GTL samples were analyzed. The results are shown in Table 1. The analysis reveals marked differences in important parameters of these fuels. Table 1. Analysis of HVO and GTL components. Start point of distillation (initial boiling point), end point of distillation (95% by volume recovered in).

Example 3:

Two diesel blends with a base cetane level of approximately 42 were prepared. One contained renewable paraffinic diesel and the second did not. Three levels of 2-EHN were tested in these mixtures. Cetane indices are presented in Table 2. The corresponding fuels were prepared with a base cetane level of approximately 48 and the 2-EHN cetane responses were measured accordingly (Results in Table 3). The increase in Cetane number of a composition comprising GTL or renewable fuel and 2-EHN using two doses of 2-EHN. The results are illustrated in Fig. 2 which shows a greater increase in cetane number in blends comprising renewable fuel compared to blends comprising GTL. 2-EHN has also been shown to increase the cetane number at different levels of 2-EHN.

Table 2: Cetane Responses with Various Dosage Rates of 2-EHN, Base Diesel Cetane Index ~ 42.

Table 3. Cetane Responses at Various Dosage Rates of 2-EHN, Base Diesel Cetane Index ~ 48

In all cases, fuels containing renewable paraffinic diesel showed a higher 2-EHN cetane response. The results are shown in Figures 3 and 4.

As a conclusion, a lower dosage of cetane index improver is required in fuels containing renewable paraffinic diesel in order to achieve the goal of the cetane number. In addition to meeting the cetane number requirements in EN590: 2013 (5.5.2) and ASTM D975 2017, it is beneficial for producing premium diesel grades with a higher cetane number.

The foregoing description has been provided by way of non-limiting examples of particular implementations and embodiments of the invention, a complete and informative description of the best mode currently contemplated by the inventors to carry out the invention. However, it is clear to a person skilled in the art that the invention is not limited to the details of the embodiments presented above, but can be implemented in other embodiments using equivalent means without deviating from the characteristics of the invention.

Furthermore, some of the features of the above-described embodiments of this invention can be used to advantage without the corresponding use of other features. As such, the foregoing description should be considered merely illustrative of the principles of the present invention, and not as a limitation thereof. Therefore, the scope of the invention is only restricted by the appended claims.

Claims (15)

1. A method of manufacturing a diesel fuel composition, comprising to. a hydrotreating step, comprising catalytically hydrotreating renewable raw material comprising fatty acids, triglycerides, fatty acid esters or combinations thereof in n-paraffins; b. an isomerization step, which comprises catalytically isomerizing the n-paraffins into branched-chain paraffins to obtain a hydrotreated renewable fuel component, wherein the amount of the paraffin component in the C ¹⁵ -C ¹⁸ carbon number range is at least 70 % by weight, and the iparaffin / n-paraffin ratio of the hydrotreated renewable component is at least 2.2 w / w; c. adding a fossil fuel component to the hydrotreated renewable fuel component; and d. add 2-EHN at a concentration in the range of 100-1000 mg / kg; where stage b. It is carried out in the absence of the hydrotreating catalyst used in step a. The method of claim 1, wherein the renewable raw material comprises vegetable oil, wood and / or other vegetable based oil, animal fat, fish fat and / or fish oil, seaweed oil, microbial oil, fats contained in plants obtained through genetic manipulation, recyclable waste, recyclable waste or a combination thereof. The method of claim 1 or 2, wherein the renewable raw material comprises rapeseed oil, rapeseed oil, canola oil, stem oil, sunflower oil, soybean oil, hemp oil, olive oil, flaxseed oil, mustard oil, palm oil, peanut oil, castor oil, coconut oil, lard, tallow, grain, milk fats, or a combination thereof. The method of any one of claims 1-3, wherein in the hydrotreated renewable fuel component, the amount of the paraffinic component in the C ¹⁵ -C ¹⁸ carbon number range is more than 80% by weight, plus preferably more than 90% by weight. The method of any one of claims 1-4, wherein the i-paraffin / n-paraffin ratio of the hydrotreated renewable component is at least 2.3 w / w, at least 3 w / w or at least 4 p / p. 6. The method of any one of claims 1-5, wherein the renewable raw material is fed to the hydrotreating step a. in a feed comprising less than 10 p-ppm of alkali metals and alkaline earth metals calculated as elemental alkali metals and elemental alkaline earth metals, less than 10 p-ppm of other metals calculated as elemental metals and less than 30 p-ppm of phosphorus calculated as phosphorus. The method of claim 6, wherein the feed comprises a fresh feed of the renewable raw material and a feed of a diluent agent, and wherein the diluent: fresh feed ratio is 10-30: 1 , preferably 12-25: 1, and wherein the diluting agent is selected from hydrocarbons and recycled products of the process, or a mixture thereof. 8. A diesel fuel component comprising a hydrotreated renewable fuel component and 100-1000 mg / kg of 2-EHN, wherein in the hydrotreated renewable fuel component the amount of the paraffinic component is in a range of carbon numbers C ¹⁵ -C ¹⁸ is at least 70% by weight and the i-paraffin / n-paraffin ratio of the hydrotreated renewable component is at least 2.2 w / w. The diesel fuel component of claim 8, wherein in the hydrotreated renewable fuel component, the i-paraffin / n-paraffin ratio of the hydrotreated renewable component is at least 2.3 p / p, at least 3 p / p or at least 4 p / p. The diesel fuel component of claim 8 or 9 having a cloud point of at least -10 ° C. 11. A use of the diesel fuel component of any one of claims 8-10 to increase the cetane number and improve the cold properties of a diesel fuel. The use of claim 11, wherein the amount of the diesel fuel component in the diesel fuel is selected from the range of 5-90% by volume, more preferably from the range of 20-80% by volume. The use of any one of claims 11-12, wherein the diesel fuel is fossil fuel, renewable fuel, or a mixture comprising fossil fuel and renewable fuel. 14. A fuel composition, comprising: to. the diesel fuel component of any one of claims 8-10; Y b. a fossil fuel component. The fuel composition of claim 14, wherein the content of the hydrotreated renewable fuel component in the fuel composition is in the range of 5-90% by volume, more preferably in the range of 20-80% by volume. .